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1.
Arch. Soc. Esp. Oftalmol ; 97(11): 646-654, nov. 2022. ilus
Artigo em Espanhol | IBECS | ID: ibc-212046

RESUMO

Introducción: La supervivencia de los niños prematuros es cada vez más frecuente siendo cada vez más habitual encontrar pacientes con este antecedente en las consultas de oftalmología. El parto prematuro puede conllevar cambios estructurales a nivel ocular, pudiéndose afectar entre otras estructuras el complejo de células ganglionares (CCG), que puede ser estudiado mediante la tomografía de coherencia óptica.Materiales y métodosRealizar una revisión bibliográfica de los estudios que analizan el CCG en pacientes con antecedente de prematuridad y lo comparan con pacientes nacidos a término.ResultadosSe referencian varios estudios que analizan el CCG en población con antecedente de prematuridad y se estudian los distintos resultados obtenidos.ConclusionesEn nuestra práctica clínica, conocer el antecedente de prematuridad es fundamental en la valoración del CCG medido por tomografía de coherencia óptica ya que el grosor de esta capa es distinta en la población con antecedente de prematuridad comparada con la población a término. (AU)


Introduction: Premature children birth and survival is becoming more frequent due to the improvement in obstetric and neonatal care. This makes it increasingly common to find patients with history of preterm birth in ophthalmology clinics, both in pediatric and adult ages. Premature birth can lead to ocular structural changes, being possible to affect the ganglion cell complex (GCC), among other structures, which can be studied using optical coherence tomography.Materials and methodsTo carry out a bibliographic review of the studies that analyze GCC in patients with a history of prematurity compared with patients born at term.ResultsSeveral studies that analyze GCC in patients with a history of prematurity are referenced and their results are studied.ConclusionsIn our clinical practice, knowing the history of prematurity is fundamental in the assessment of GCC measured by optical coherence tomography, since this layer is different in the patients with a history of prematurity compared to patients born at term. (AU)


Assuntos
Humanos , Recém-Nascido , Células Ganglionares da Retina , Retinopatia da Prematuridade , Recém-Nascido Prematuro , Idade Gestacional , Peso ao Nascer , Tomografia de Coerência Óptica , Acuidade Visual
2.
Artigo em Inglês | MEDLINE | ID: mdl-36075825

RESUMO

INTRODUCTION: Premature children birth and survival is becoming more frequent due to the improvement in obstetric and neonatal care. This makes it increasingly common to find patients with history of preterm birth in ophthalmology clinics, both in pediatric and adult ages. Premature birth can lead to ocular structural changes, being possible to affect the ganglion cell complex (GCC), among other structures, which can be studied using optical coherence tomography. MATERIALS AND METHODS: To carry out a bibliographic review of the studies that analyze GCC in patients with a history of prematurity compared with patients born at term. RESULTS: Several studies that analyze GCC in patients with a history of prematurity are referenced and their results are studied. CONCLUSIONS: In our clinical practice, knowing the history of prematurity is fundamental in the assessment of GCC measured by optical coherence tomography, since this layer is different in the patients with a history of prematurity compared to patients born at term.

3.
Opt Express ; 28(20): 29054-29063, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-33114811

RESUMO

A diffractive optical element was fabricated by monolithically integrating two volume phase-gratings (VPGs) in the bulk of a single-piece transparent material. A computer model of the diffraction generated by the double volume phase-grating (DVPG) was made with a rigorous coupled wave analysis simulator. Simulations and experiments show that the diffractive behavior of a DVPG can be controlled by arranging the relative displacement and the distance between the VPGs according to Talbot self-imaging planes. In order to diffract the total incident light, the phase accumulation in the VPGs has to be π/2, which was achieved by single-scan femtosecond laser processing of a nanocrystal doped glass as the substrate material. Ex situ microscope images of the cross-sections are presented for laser processed lines in the form of VPGs and DVPGs. The far-field diffraction of DVPGs formed by selectively located VPGs was characterized with a monochromatic 633 nm and a supercontinuum white light. Functional designs of high diffraction efficiency with potential applications in photonics were successfully fabricated in a one-step and free of chemicals process.

4.
eNeuro ; 7(2)2020.
Artigo em Inglês | MEDLINE | ID: mdl-32188709

RESUMO

In the auditory system, the spectrotemporal structure of acoustic signals determines the temporal pattern of spikes. Here, we investigated this effect in neurons of the barn owl's auditory midbrain (Tyto furcata) that are selective for auditory space and whether it can influence the coding of sound direction. We found that in the nucleus where neurons first become selective to combinations of sound localization cues, reproducibility of spike trains across repeated trials of identical sounds, a metric of across-trial temporal fidelity of spiking patterns evoked by a stimulus, was maximal at the sound direction that elicited the highest firing rate. We then tested the hypothesis that this stimulus-dependent patterning resulted in rate co-modulation of cells with similar frequency and spatial selectivity, driving stimulus-dependent synchrony of population responses. Tetrodes were used to simultaneously record multiple nearby units in the optic tectum (OT), where auditory space is topographically represented. While spiking of neurons in OT showed lower reproducibility across trials compared with upstream nuclei, spike-time synchrony between nearby OT neurons was highest for sounds at their preferred direction. A model of the midbrain circuit explained the relationship between stimulus-dependent reproducibility and synchrony, and demonstrated that this effect can improve the decoding of sound location from the OT output. Thus, stimulus-dependent spiking patterns in the auditory midbrain can have an effect on spatial coding. This study reports a functional connection between spike patterning elicited by spectrotemporal features of a sound and the coding of its location.


Assuntos
Localização de Som , Estrigiformes , Estimulação Acústica , Animais , Vias Auditivas , Percepção Auditiva , Reprodutibilidade dos Testes
5.
Mult Scler Relat Disord ; 41: 102017, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32120027

RESUMO

Teriflunomide is an oral first-line disease modifying treatment (DMT) for patients with relapsing-remitting multiple sclerosis (RRMS). It can take up to two years to achieve systemic clearance of teriflunomide to an acceptable level, but this washout period may be accelerated by administration of cholestyramine. Relapse of multiple sclerosis (MS) during washout of teriflunomide or other first-line DMT is not as common. We report two patients with RRMS who experienced a relapse after the accelerated elimination period (AEP) of teriflunomide and confirmation of negative plasmatic levels (<0.02 µg/ml). In cases of risk of MS activity, we should not wait for teriflunomide negative plasmatic levels confirmation before starting the next DMT to reduce the risk of relapse.


Assuntos
Crotonatos/farmacocinética , Fatores Imunológicos/farmacocinética , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Esclerose Múltipla Recidivante-Remitente/fisiopatologia , Toluidinas/farmacocinética , Adulto , Resinas de Troca Aniônica/administração & dosagem , Resina de Colestiramina/administração & dosagem , Crotonatos/sangue , Feminino , Humanos , Hidroxibutiratos , Fatores Imunológicos/sangue , Masculino , Nitrilas , Recidiva , Toluidinas/sangue
6.
Rev Clin Esp (Barc) ; 218(9): 468-476, 2018 Dec.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30177223

RESUMO

INTRODUCTION: Hereditary hemorrhagic telangiectasia (HHT) is a rare disease with autosomal dominant inheritance that causes systemic vascular affectation. MATERIAL AND METHOD: After development a multicentric Spanish national registry, called RiHHTa, main clinical manifestations and diagnostic procedures of the first patients introduced are described. RESULTS: 141 patients were included, of which 91 (64.5%) were women. The mean age at diagnosis was 42 years. Mutations in the ACVRL1 gene predominated over the ENG gene. The initial symptom was recurrent epistaxis in 130 (92.2%) patients and in three (2.1%), brain abscess. Pulmonary arteriovenous (AV) fistula were detected in 36 (45%) of the 79 patients who underwent thoracic CT angiography. The contrast echocardiography detected very few bubbles (grade I) or none, in 36 (45%) of these 79 affected patients. In 43 (67.2%) of the 64 patients with an abdominal CT angiography, hepatic vascular malformations were detected, mostly telangiectasias, AV and arterio-portal fistula, and extrahepatic in 14 (10%) subjects. More than half of the patients were screened for the presence of brain arteriovenous malformations which was found in 3.9% of them. The upper part of the intestinal tube was the most (95%) affected region. CONCLUSION: The RiHHTa Registry allows improving the management of patients with HHT. An inadequate use of thoracic CT angiography and the usefulness of abdominal CT angiography has been detected in order to define subtypes of hepatic vascular involvement and detect extrahepatic vascular involvement.

10.
Rev Clin Esp (Barc) ; 217(2): 108-116, 2017 Mar.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-27702442

RESUMO

Autoinflammatory diseases are clinical conditions with inflammatory manifestations that present in a periodic or persistent manner and are caused by acquired or hereditary disorders of the innate immune response. In general, these diseases are more common in childhood, but cases have been reported in adults and are therefore important for all specialists. There are few references on these diseases in adults due to their low prevalence and underdiagnosis. The aim of this study is to review the scientific literature on these disorders to systematise their clinical, prognostic and treatment response characteristics in adults.

11.
Rev Clin Esp (Barc) ; 216(3): 146-56, 2016 Apr.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-26749192

RESUMO

Castleman's disease is not just a single disease but rather an uncommon, heterogeneous group of nonclonal lymphoproliferative disorders, which have a broad spectrum of clinical expression. Three histological types have been reported, along with several clinical forms according to clinical presentation, histological substrate and associated diseases. Interleukin-6, its receptor polymorphisms, the human immunodeficiency virus and the human herpes virus 8 are involved in the etiopathogenesis of Castleman's disease. The study of this disease has shed light on a syndrome whose incidence is unknown. Despite recent significant advances in our understanding of this disease and the increasing therapeutic experience with rituximab, tocilizumab and siltuximab, there are still difficult questions concerning its aetiology, prognosis and optimal treatment.

12.
Mol Psychiatry ; 21(9): 1208-14, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26666205

RESUMO

A critical step toward understanding autism spectrum disorder (ASD) is to identify both genetic and environmental risk factors. A number of rare copy number variants (CNVs) have emerged as robust genetic risk factors for ASD, but not all CNV carriers exhibit ASD and the severity of ASD symptoms varies among CNV carriers. Although evidence exists that various environmental factors modulate symptomatic severity, the precise mechanisms by which these factors determine the ultimate severity of ASD are still poorly understood. Here, using a mouse heterozygous for Tbx1 (a gene encoded in 22q11.2 CNV), we demonstrate that a genetically triggered neonatal phenotype in vocalization generates a negative environmental loop in pup-mother social communication. Wild-type pups used individually diverse sequences of simple and complicated call types, but heterozygous pups used individually invariable call sequences with less complicated call types. When played back, representative wild-type call sequences elicited maternal approach, but heterozygous call sequences were ineffective. When the representative wild-type call sequences were randomized, they were ineffective in eliciting vigorous maternal approach behavior. These data demonstrate that an ASD risk gene alters the neonatal call sequence of its carriers and this pup phenotype in turn diminishes maternal care through atypical social communication. Thus, an ASD risk gene induces, through atypical neonatal call sequences, less than optimal maternal care as a negative neonatal environmental factor.


Assuntos
Transtorno Autístico/genética , Proteínas com Domínio T/fisiologia , Animais , Transtorno do Espectro Autista/genética , Comunicação , Variações do Número de Cópias de DNA/genética , Modelos Animais de Doenças , Feminino , Predisposição Genética para Doença/genética , Genótipo , Heterozigoto , Masculino , Comportamento Materno , Camundongos , Fenótipo , Fatores de Risco , Comportamento Social , Relação Estrutura-Atividade , Proteínas com Domínio T/genética , Vocalização Animal
14.
Arch Soc Esp Oftalmol ; 90(6): 289-91, 2015 Jun.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-25433417

RESUMO

CASE REPORT: The case is presented of a 30 year-old man, with night blindness and decreased visual acuity (VA) in both eyes, but more significant in the left eye (LE) of 20/100. Lesions consistent with choroideremia and LE macular hemorrhage was observed in the fundus. CNV was confirmed by OCT. A definitive diagnosis was obtained by genetic study. No treatment was given as the patient did not return. At 6 months there was a regression of CNV with VA 20/25 in the LE. CONCLUSIONS: CNV associated with choroideremia is uncommon. Treatment would antiangiogenic therapy, however spontaneous resolution is possible.


Assuntos
Neovascularização de Coroide/etiologia , Coroideremia/complicações , Proteínas Adaptadoras de Transdução de Sinal/genética , Adulto , Inibidores da Angiogênese/uso terapêutico , Neovascularização de Coroide/tratamento farmacológico , Coroideremia/genética , Éxons/genética , Humanos , Masculino , Cegueira Noturna/etiologia , Hemorragia Retiniana/etiologia , Deleção de Sequência , Tomografia de Coerência Óptica
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